Leveling bridge



April 22, 1952 w. H. BOTHE LEVELING BRIDGE Filed July 1o, 195o INVENTOR.

w TIN i @j P o w@ my Patented Apr. 22, 1952 LEVELING BRIDGE Werner H. Bothe,'Ken0sha, Wis., assigner to Worldsbest Industries, Inc., Cudahy, Wis., a corporation. of Wisconsin Application July 10, 1950, Serial No. 172,954 T The invention relates to stretching frames for use in drying curtains and other fabrics.

The usual frames for stretching curtains and other fabrics include frame members extendingr at an angle to each other and one of which frame members overlies the other angularly disposed frame member with the result that the impaling pins mounted on one of these frame members are raised above or out of the plane of the impaling pins on the other frame member. In situn `ations of this kind a so-called levelling bridge or angularly disposed pin carrying plate is used to aid in clamping the fabric at the joint formed between the angularly disposed frame members. The Object of the present invention is to provide a new and improved form of levelling bridge whereby the pins of the pin plate or bridge are alined with and disposed between the pins of one of the angularly disposed members above referred to.

A further object of the invention is to provide a levelling bridge having a pin carrying plate which may be readily adjusted to assume different angular positions and which preferably may be clamped in its adjusted position by clamping means securing the levelling bridge to one of the stretcher frame members.

The invention further consists in the several features hereinafter set forth and more yparticularly defined by claims at the conclusion hereof. Y

In the drawings:

Fig. 1 is an elevation view of a stretching frame equipped with the levelling bridge embodying the invention;

Fig. 2 is a detailedvertical sectional View taken on the line 2-2 of Fig. 1;

Fig. 3 is a detailed horizontal sectional View taken on the line 3-3 of Fig. l;

Fig. 4 is a perspective View of the levelling bridge and its mounting.

Referring to the drawings, I have shown a stretching frame including a top bar 5, end bars 6, a center bar l, a bottom bar 8 lengthwise adjustably mounted relative tothe end bars 6 and secured thereto by clamping devices 9, and a vertical adjustably mounted bar I adjustably secured to the top bar by a clamping device II and to the bottom bar 8 by a clamping device IZ of known construction and by which the bar I0 is clamped against the back face of the bar 8.

The clamping devices 9 and II are shown as those of my prior U. S. Patent No. 2,448,574, dated September 7, 1948. The end bars 6 are 5 claims. (o1. 45-724') clamped in right angular relation with the top bar `5' by corner fittings I3, such as lshownv and described in my copending applicationr Serial No. 76,401, l'ed February 14, 1949, for Curtain :Stretcher Corner Structure, now Patent No. 2,519,628 of August 22, 1950. The center bar l is shown as clamped to the top and bottom bars by fittings I4, more particularly shown and described in my copending application Serial No. 772,175, led September 4, 1947, for Curtain Stretcher, now Patent No. 2,572,979 of October 30, 1951.

-From the above it will be noted that the stretching frame includes top and bottom bars, posts or end bars, and an adjusting bar clamped together by the various fittings mentioned above to form a frame, some of the bars being adjustable to accommodate curtains or fabrics of different Widths and lengths.

The top bar 5, one of the end bars 6, the bottom bar 8, and the adjusting bar I0 are each provided with a row of pins I5 on which portions of the dampy curtains or other fabrics are impaled to stretch the fabric and hold it in this condition until dried.

As previously noted, the present invention is directed to a levelling bridge used Where two of the frame bars, such as the bars 8 and IU are joined together in angularly disposed relation with the bottom bar 8 superposed over the adjusting lbar I0 and in which instance the pins I5 'ony the bar 8 are in aplane above the :pins of, the-'bar I Il. The bridge may also be used in other instances Where the planes' of the pins of the bars are vertically displaced as at the joint betweenthe top bar 5 andthe bar I@ and the joint Vbetween the pinned end bar 6 and the bo-ttorri bar 8.

Referring to the drawings, the levelling bridge comprises a .pin carrying plate I6 in the form of an angled plate having one side |I adapted to extend parallel to one of the angularly disposed bars, here shown as the bar I0, and its other side formed to provide spaced ears or projections I8 in each of which the shank of a pin I9 is mounted, the disposition of the pins I9 being such that when the side I'I of the plate I6 is brought into abutting engagement with front edge of the bar I 0, the pins I 9 will be alined with the row of pins I5 in the bar I0, and some of these pins I9 will be disposedfr-between some of the pins I5 as shown in Figs. 1 to 3. This is a desirable feature as it permits a more accurate Ipinning of the curtain, and vboth sets of pins I9 and I5 are functioning together for a portion of the length of the levelling bridge.

The levelling bridge or plate I6 may be secured in operative position in various ways by providing means :for clamping it to one of the angularly disposed bars. The preferred construction shown in the drawings is to pivotally mount the bridge I6 by means of a pin 2B on the inner side of an angularly disposed side or leg 2| of a metal slide fitting or supporting bracket 22 whose opposite side 23 forms the web of a channel 24 within which the bar I 0 is slidably mounted. For clamping the bracket 22 in lengthwise adjusted position on the bar IS and also for simultaneously clamping the bridge I6 in the desired angularly adjusted position relative to the bars 8 and I0, a threaded screw 25 is anchored in the web 23 of the bracket 22 and extends through an aperture 26 in a U-shaped clamping head or jaw member 21 having angled feet 28 to engage the back edge of the bar Ill, and a clamping nut 29, such as a wing nut, is -mounted on the threaded end of the screw 25.

With the4 above construction, the bracket 22 with its attached bridge member I6 is slid over the lower end of the bar I0 before the said bar is clamped to the bar 8 by the clamping device I2. After the bottom bar 8 has been clamped to the bar I9 as shown in Fig. l, the bracket 22 is moved along the bar I9 to the position shown in Fig. 1, and the bridge plate I6 is tipped 0n its pivot to the desired angle, as for example, that shown in Fig. 2, and then the nut 29 is screwed up on the screw 25 bringing the clamping member 27 against the back edge of the bar and drawing the body of the plate I6 against the front edge of the bar. In this position the pins I9 of the bridge plate I8 align with the pins I5 of the bar I0 and provide an inclined pinning path from the pins of the bar IB to the pins of the bar 8 upon which the fabric may be impaled, thus eliminating the unpinned gap which occurs without a levelling bridge and improving the corner pinning anchorage for the curtain.

I desire it to be understood that this invention is not to be limited to any particular form or arrangement of parts except in so far as such limitations are included in the claims.

What I claim as my invention is:

l. In a stretching frame having angularly disposed and joined pin carrying frame members with one of said frame members overlying the other frame member, the combination of a support, means for clamping said support to one of said frame members, and a levelling bridge pivotally mounted on a horizontal axis on said support at one side thereof and provided with pins alining with the pinning of one of said frame members and simultaneously active therewith and forming an inclined pinning path between the pinning of said members.

2. The structure as claimed in claim 1 wherein the levelling bridge on said support is clamped against one of said frame members when said support is clamped in position.

3. In a. stretching frame having angularly disposed and joined pin carrying frame members with one of said frame members overlying the other frame member, the combination of a channelled bracket slidably mounted on one of said frame members and having an angled side adjacent the front edge of said frame member, a pin carrying levelling bridge pivotally mounted on said angled side between said side and the front edge of said frame member, said bridge bing disposable relative to said frame members to provide a pinning path between the pinning of said members, and means for clamping said bracket to said frame member.

4. The structure as dened in claim 3 wherein the means for clamping the bracket to said frame member comprises a screw anchored to said bracket, a clamping head engageable with the back edge of said frame member and through which said screw passes, and a clamping nut mounted on said screw and engageable with said clamping head.

5. In a stretching frame having angularly dis posed and joined pin carrying frame members with one of said frame members overlying the other frame member, a levelling bridge mounted on one of said frame members and provided with pins alning with the pinning of one of said frame members and forming an inclined pinning path between the pinning of said members, said bridge comprising an angled member, one of whose sides extends parallel to and abuts the front edge of the frame member having the pinning alined with that on said bridge and the other side has spaced ears in which the pins are mounted, some of said ears lying between the pins on said frame member so that the pins on these ears are simultaneously active with the pins of the meinber having the alined pinning.

WERNER H. BOTHE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,929,629 Dougherty Oct. 10, 1933 2,236,745 Block Apr. l, 1941 2,279,647 Watling Apr. le, 1942 

